Screw injection molding device

Abstract

The invention provides a screw injection molding device. The device comprises a storage hopper, a plasticizing injection unit communicated with the interior of the storage hopper and a molding unit communicated with an injection nozzle of the plasticizing injection unit. The device is characterized in that the plasticizing injection unit comprises a material barrel communicated with the interior of the storage hopper, a screw penetrating the material barrel and arranged coaxially with the material barrel and a motor driving the screw to rotate around the own axis. A plurality of screw grooves for pushing materials are opened spirally in the outer wall of the screw, and a heating unit is arranged on the outer wall of the material barrel. According to the screw injection molding device, powder is pushed from an inlet to the injection nozzle through the rotation of the screw with the screw grooves and is stirred and mixed fully during rotation, so that the powder is uniformly heated under the action of the heating unit, and the 'laminar-flow'-shaped motion problem of the powder is solved; shear heat is generated for the powder by the rotation screw grooves, so that the powder temperature is further improved, and the powder is in a uniform viscous state before reaching the front end of the material barrel.

Description

technical field [0001] The invention relates to an injection molding device, in particular to a screw-pushed injection molding device, which is suitable for metal powder injection molding and belongs to the technical field of powder metallurgy. Background technique [0002] Metal powder injection molding technology is a new powder metallurgy molding technology formed by introducing modern plastic injection molding technology into the field of powder metallurgy. The basic process is as follows: firstly, the solid powder and organic binder are evenly mixed, and after granulation, they are injected into the cavity of the mold with an injection molding machine to solidify and molded in a heated and plasticized state, and then chemically or thermally decomposed. The binder in the forming blank is removed, and finally the final product is obtained through sintering and densification. Compared with the traditional process, it has the characteristics of high precision, uniform stru...

AI Technical Summary

Problems solved by technology

The injection device commonly used at present has the problem of uneven melting, which is specifically manifested as: because there is no structure for mixing the powder in the injection device, the powder moves in a "laminar flow" state in the barrel, causing the powder to move close to the barrel. The powder on the wall has a high temperature and melts quickly, while the powder in the center of the barrel has a low temperature and melts slowly

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